This invention is related to cotton harvesters and other vehicles, such as high dump wagons, of the type having a crop receiving receptacle or basket mounted thereon which elevates and dumps the cotton or other crop to the side of the vehicle into a high walled receptacle, for example, a cotton module builder, and more particularly, to an improvement in the hydraulic lift apparatus for the basket wherein a special linear hydraulic motor design is utilized which will permit the safe handling of the loaded basket while allowing rods of smaller diameter to be used.
Previous cotton harvesters, such as that described in U.S. Pat. No. 4,059,942, have utilized a pair of simple hydraulic cylinders or linear motors interconnecting the basket and harvester frame at the front and rear ends of the basket which extend to cause the basket to elevate and pivot about a horizontal axis near the top of the basket. Typically, the stroke of the motor in this application is quite long and the load is substantial. Although the required stroke and lifting force are the determining factors of the length of the cylindrical housing and the piston diameter in a given hydraulic system, in basket lifting applications, the stroke is so long that the diameter of the rod is primarily influenced by its ability to withstand buckling rather than its strength in compression.
In the referenced copending application, Ser. No. 219,404, an improved linear hydraulic motor is provided to reduce the buckling effect encountered with simple cylinders, the improved linear motor including a pair of rod-piston assemblies pivotally attached respectively to the frame and the basket and a floating axially unrestrained housing slidably receiving the two pistons. However, while the improved tandem linear motor performs satisfactorily, the housing has a tendency to rotate during operation which may stress the hydraulic supply lines and may also cause interference between the radially projecting hydraulic connectors on the cylinder housings and the adjacent structures of the basket or harvester frame.